CG Products XR1-E, Быстрый старт, Страница: 6 / 8

About Ring Modulation
Ring modulation is the multiplication of two bipolar audio signals by each other. Each value of a
carrier signal,
C , is multiplied by a modulator signal, M , to create a new ring-modulated signal, R :
R(t) = C(t)
x
M(t)
(from: http://en.wikibooks.org/wiki/Sound_Synthesis_Theory/Modulation_Synthesis )
It is referred to as "ring" modulation because the analog circuit of diodes originally used to
implement this technique took the shape of a ring (
Wikipedia ).
For example: If one or both of the input signals C or M is 0V, the output R will be also 0V.
Note: In the case of the XR1-E the carrier signal is or , provided by the internal oscillator.
Examples
Input (=modulator) signal frequency >> oscillator (carrier) frequency ( ):
Input signal: metallophone
The volume of the metallophone sound varies with the oscillator amplitude.
Input (=modulator) signal frequency << oscillator (carrier) frequency ( )
Input signal: "Base drum" from rhythm machine The generated effect signal
The volume of the oscillator sound varies with the amplitude of the input signal
Input (=modulator) signal frequency ≤ or ≥ oscillator (carrier) frequency ( )
Input signal: "Mid tom" from rhythm machine
Complexe sound structures are generated, depending on the oscillator pitch.
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